{"id":1538,"date":"2026-04-27T13:50:10","date_gmt":"2026-04-27T13:50:10","guid":{"rendered":"https:\/\/shatranj.ai\/?page_id=1538"},"modified":"2026-04-28T13:42:40","modified_gmt":"2026-04-28T13:42:40","slug":"suli-diamond","status":"publish","type":"page","link":"https:\/\/shatranj.ai\/de\/suli-diamond\/","title":{"rendered":"Suli's Diamant"},"content":{"rendered":"\t\t<div data-elementor-type=\"wp-page\" data-elementor-id=\"1538\" class=\"elementor elementor-1538\" data-elementor-post-type=\"page\">\n\t\t\t\t<div data-pafe-particles=\"6b6e801\" data-pafe-particles-options=\"{&quot;quantity&quot;:300,&quot;particles_color&quot;:&quot;#FFFFFF&quot;,&quot;linked_color&quot;:&quot;#FFFFFF&quot;,&quot;hover_effect&quot;:&quot;&quot;,&quot;click_effect&quot;:&quot;&quot;,&quot;particles_shape&quot;:&quot;circle&quot;,&quot;particles_size&quot;:3,&quot;particles_speed&quot;:2,&quot;particles_image&quot;:&quot;https:\\\/\\\/shatranj.ai\\\/wp-content\\\/plugins\\\/elementor\\\/assets\\\/images\\\/placeholder.png&quot;,&quot;particles_opacity&quot;:{&quot;unit&quot;:&quot;px&quot;,&quot;size&quot;:0.3,&quot;sizes&quot;:[]},&quot;linked_opacity&quot;:0.3}\" class=\"elementor-element elementor-element-6b6e801 e-flex e-con-boxed e-con e-parent\" data-id=\"6b6e801\" data-element_type=\"container\" data-settings=\"{&quot;background_background&quot;:&quot;classic&quot;}\">\n\t\t\t\t\t<div class=\"e-con-inner\">\n\t\t\t\t<div class=\"elementor-element elementor-element-44c20db elementor-widget elementor-widget-heading\" data-id=\"44c20db\" data-element_type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t<style>\/*! elementor - v3.21.0 - 08-05-2024 *\/\n.elementor-heading-title{padding:0;margin:0;line-height:1}.elementor-widget-heading .elementor-heading-title[class*=elementor-size-]>a{color:inherit;font-size:inherit;line-height:inherit}.elementor-widget-heading .elementor-heading-title.elementor-size-small{font-size:15px}.elementor-widget-heading .elementor-heading-title.elementor-size-medium{font-size:19px}.elementor-widget-heading .elementor-heading-title.elementor-size-large{font-size:29px}.elementor-widget-heading .elementor-heading-title.elementor-size-xl{font-size:39px}.elementor-widget-heading .elementor-heading-title.elementor-size-xxl{font-size:59px}<\/style><h1 class=\"elementor-heading-title elementor-size-default\">Suli&#8217;s Diamond<\/h1>\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t<div class=\"elementor-element elementor-element-009eae8 e-con-full e-flex e-con e-parent\" data-id=\"009eae8\" data-element_type=\"container\">\n\t\t\t\t<div class=\"elementor-element elementor-element-e2f2b94 elementor-widget elementor-widget-text-editor\" data-id=\"e2f2b94\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t<style>\/*! elementor - v3.21.0 - 08-05-2024 *\/\n.elementor-widget-text-editor.elementor-drop-cap-view-stacked .elementor-drop-cap{background-color:#69727d;color:#fff}.elementor-widget-text-editor.elementor-drop-cap-view-framed .elementor-drop-cap{color:#69727d;border:3px solid;background-color:transparent}.elementor-widget-text-editor:not(.elementor-drop-cap-view-default) .elementor-drop-cap{margin-top:8px}.elementor-widget-text-editor:not(.elementor-drop-cap-view-default) .elementor-drop-cap-letter{width:1em;height:1em}.elementor-widget-text-editor .elementor-drop-cap{float:left;text-align:center;line-height:1;font-size:50px}.elementor-widget-text-editor .elementor-drop-cap-letter{display:inline-block}<\/style>\t\t\t\t<section class=\"suli-page\"><style>.suli-page{--ink:#17212b;--muted:#5d6b7a;--gold:#b8872f;--sand:#f7f1e6;--paper:#fffaf0;--line:#eadcc7;--deep:#102033;font-family:inherit;color:var(--ink);line-height:1.65}.suli-page *{box-sizing:border-box}.suli-wrap{max-width:1120px;margin:0 auto;padding:28px 18px}.suli-hero{background:linear-gradient(135deg,#101c2b 0%,#203852 55%,#6f4d1f 100%);color:#fff;border-radius:24px;padding:52px 34px;box-shadow:0 18px 50px rgba(0,0,0,.16);overflow:hidden;position:relative}.suli-hero:after{content:\"\";position:absolute;right:-70px;top:-70px;width:220px;height:220px;border:1px solid rgba(255,255,255,.22);transform:rotate(45deg)}.suli-kicker{text-transform:uppercase;letter-spacing:.12em;color:#f4d38b;font-size:.82rem;font-weight:700;margin-bottom:10px}.suli-hero 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img{width:100%;display:block;background:#fff}.suli-main-diagram-caption{padding:16px 18px 18px;border-top:1px solid var(--line)}.suli-main-diagram-caption h3{margin:0 0 4px;color:var(--deep);font-size:1.2rem;line-height:1.2}.suli-main-diagram-caption p{margin:0 0 10px;color:var(--muted);font-size:.96rem}.suli-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:16px;margin-top:20px}.suli-card{background:#fff;border:1px solid var(--line);border-radius:18px;padding:20px;box-shadow:0 8px 26px rgba(16,32,51,.06)}.suli-card h3{margin:0 0 8px;font-size:1.08rem;color:var(--deep)}.suli-card p{margin:0;color:var(--muted)}.suli-callout{background:var(--sand);border-left:5px solid var(--gold);border-radius:18px;padding:22px;margin:24px 0}.suli-callout p{margin:0;color:var(--muted)}.suli-fen{display:block;background:#111923;color:#f5e6c7;padding:12px 14px;border-radius:12px;font-family:ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;font-size:.9rem;overflow-x:auto;margin-top:10px;white-space:nowrap}.suli-video{position:relative;padding-bottom:56.25%;height:0;overflow:hidden;border-radius:22px;box-shadow:0 16px 40px rgba(0,0,0,.18);background:#000;margin-top:22px}.suli-video iframe{position:absolute;top:0;left:0;width:100%;height:100%;border:0}.suli-chapters{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:14px;margin-top:22px}.suli-chapter{background:var(--paper);border:1px solid var(--line);border-radius:16px;padding:16px}.suli-time{display:inline-block;font-weight:800;color:#7a4e0b;margin-bottom:4px}.suli-chapter h3{margin:0 0 6px;font-size:1.02rem;color:var(--deep)}.suli-chapter p{margin:0;color:var(--muted);font-size:.96rem}.suli-play-callout{background:linear-gradient(135deg,#f7f1e6 0%,#fffaf0 100%);border:1px solid var(--line);border-left:5px solid var(--gold);border-radius:18px;padding:22px;margin:24px 0}.suli-play-callout h3{margin:0 0 8px;color:var(--deep);font-size:1.25rem}.suli-play-callout p{margin:0 0 14px;color:var(--muted)}.suli-play-callout a{display:inline-block;padding:10px 16px;border-radius:999px;background:var(--deep);color:#fff;text-decoration:none;font-weight:700}.suli-position-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:18px;margin-top:24px}.suli-position-card{background:#fff;border:1px solid var(--line);border-radius:1px;overflow:hidden;box-shadow:none}.suli-position-card img{width:100%;display:block;background:#fff;border-bottom:1px solid var(--line)}.suli-position-body{padding:18px}.suli-position-body h3{margin:0 0 4px;color:var(--deep);font-size:1.16rem;line-height:1.2}.suli-position-subtitle{margin:0 0 10px;color:#8a5a12;font-weight:700;font-size:.94rem}.suli-position-body p{color:var(--muted);margin:0 0 14px;font-size:.96rem}.suli-meta{display:flex;flex-wrap:wrap;gap:8px;margin:0 0 10px}.suli-meta span{display:inline-block;background:#f3eadb;color:#203046;border-radius:999px;padding:5px 10px;font-size:.82rem;font-weight:700}.suli-links{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:14px;margin-top:18px}.suli-linkbox{display:block;text-decoration:none;color:var(--ink);background:#fff;border:1px solid var(--line);border-radius:16px;padding:18px;transition:transform .15s ease,box-shadow .15s ease}.suli-linkbox:hover{transform:translateY(-2px);box-shadow:0 10px 24px rgba(16,32,51,.10)}.suli-linkbox strong{display:block;color:var(--deep);margin-bottom:5px}.suli-linkbox span{color:var(--muted)}.suli-faq details{background:#fff;border:1px solid var(--line);border-radius:14px;padding:16px 18px;margin-bottom:10px}.suli-faq summary{cursor:pointer;font-weight:800;color:var(--deep)}.suli-faq p{color:var(--muted);margin:10px 0 0}@media(max-width:980px){.suli-position-grid{grid-template-columns:repeat(2,minmax(0,1fr))}.suli-intro-layout{grid-template-columns:1fr}}@media(max-width:820px){.suli-grid,.suli-chapters,.suli-links{grid-template-columns:1fr}.suli-hero{padding:38px 22px}}@media(max-width:640px){.suli-position-grid{grid-template-columns:1fr}.suli-wrap{padding-left:14px;padding-right:14px}}<\/style>\n<div class=\"suli-wrap\"><header class=\"suli-hero\">\n<div class=\"suli-kicker\">Shatranj \u2022 Chess history \u2022 Artificial intelligence<\/div>\n<h1>Suli\u2019s Diamond<\/h1>\nSuli\u2019s Diamond is the mysterious 1000-year unsolved chess puzzle associated with the challenge of the legendary chess master as-Suli. Preserved through medieval manuscripts and later reconstructed by modern historians, endgame experts, and computer analysis, it remains one of the most beautiful intellectual challenges in chess history.\n<div class=\"suli-buttons\"><a class=\"suli-btn primary\" href=\"#watch\">Watch the video<\/a>\n<a class=\"suli-btn secondary\" href=\"#contents\">Video contents<\/a>\n<a class=\"suli-btn secondary\" href=\"#positions\">See the positions<\/a>\n<a class=\"suli-btn secondary\" href=\"https:\/\/doi.org\/10.5281\/zenodo.19465731\" target=\"_blank\" rel=\"noopener\">Read the paper<\/a>\n<a class=\"suli-btn secondary\" href=\"https:\/\/play.shatranj.ai\" target=\"_blank\" rel=\"noopener\">Try on play.shatranj.ai<\/a><\/div>\n<\/header><section class=\"suli-section suli-intro-tight-section\"><style>\n  .suli-intro-tight-section .suli-intro-layout {<br \/>    display: grid;<br \/>    grid-template-columns: minmax(0, 1.08fr) minmax(280px, 420px);<br \/>    gap: 28px;<br \/>    align-items: center;<br \/>  }<\/p>\n<p>  .suli-intro-tight-section .suli-lead {<br \/>    margin-bottom: 14px;<br \/>  }<\/p>\n<p>  .suli-intro-tight-section .suli-card-stack {<br \/>    display: grid;<br \/>    grid-template-columns: 1fr;<br \/>    gap: 14px;<br \/>    margin-top: 18px;<br \/>  }<\/p>\n<p>  .suli-intro-tight-section .suli-challenge,<br \/>  .suli-intro-tight-section .suli-card {<br \/>    background: #fff;<br \/>    border: 1px solid var(--line);<br \/>    border-radius: 16px;<br \/>    padding: 16px;<br \/>    box-shadow: 0 8px 22px rgba(16,32,51,.06);<br \/>  }<\/p>\n<p>  .suli-intro-tight-section .suli-challenge {<br \/>    background: #fffaf0;<br \/>    border-left: 4px solid var(--gold);<br \/>  }<\/p>\n<p>  .suli-intro-tight-section .suli-challenge h3,<br \/>  .suli-intro-tight-section .suli-card h3 {<br \/>    margin: 0 0 8px;<br \/>    color: var(--deep);<br \/>    font-size: 1.04rem;<br \/>  }<\/p>\n<p>  .suli-intro-tight-section .suli-challenge p,<br \/>  .suli-intro-tight-section .suli-card p {<br \/>    margin: 0;<br \/>    color: var(--muted);<br \/>    font-size: .93rem;<br \/>    line-height: 1.48;<br \/>  }<\/p>\n<p>  .suli-intro-tight-section .suli-challenge p {<br \/>    font-style: italic;<br \/>  }<\/p>\n<p>  .suli-intro-tight-section .suli-main-diagram {<br \/>    max-width: 420px;<br \/>    justify-self: center;<br \/>  }<\/p>\n<p>  @media (max-width: 980px) {<br \/>    .suli-intro-tight-section .suli-intro-layout {<br \/>      grid-template-columns: 1fr;<br \/>      align-items: start;<br \/>    }<\/p>\n<p>    .suli-intro-tight-section .suli-main-diagram {<br \/>      max-width: 520px;<br \/>      width: 100%;<br \/>    }<br \/>  }<br \/><\/style>\n<div class=\"suli-intro-layout\">\n<div>\n<h2>What is Suli\u2019s Diamond?<\/h2>\n<p class=\"suli-lead\">Suli\u2019s Diamond is a four-piece endgame from shatranj, the historical form of chess. Each side has a shah and a ferz. The shah moves like the modern king. The ferz, or vizier, moves only one square diagonally.<\/p>\n<p class=\"suli-lead\">White\u2019s task is to capture Black\u2019s cornered ferz without allowing Black\u2019s shah to capture White\u2019s ferz in return. The position looks simple, but its solution requires opposition, triangulation, zugzwang, corresponding squares, and a shouldering race maneuver or shahs across the board.<\/p>\n\n<div class=\"suli-card-stack\">\n<div class=\"suli-challenge\" style=\"background: #fffaf0; border: 1px solid #eadcc7; border-left: 4px solid #b8872f; border-radius: 16px; padding: 16px; box-shadow: 0 8px 22px rgba(16,32,51,.06);\">\n<h3 style=\"margin: 0 0 8px; color: #102033; font-size: 1.04rem;\">As-Suli\u2019s challenge<\/h3>\n<p style=\"margin: 0; color: #5d6b7a; font-size: .93rem; line-height: 1.48; font-style: italic;\">This position is ancient old, yet neither al-\u2018Adli nor any one else has said whether it is drawn or can be won. Nor has any one interpreted it, or pointed (diagrammed) it because of its difficulty. There is no one on earth who has solved it unless he was taught it by me. I have never learnt that there was any one before; for if any one had solved it, he would either have written down the solution, or have taught it to some one else. This is the word of As-Suli. (9th century)<\/p>\n\n<\/div>\n<div class=\"suli-card\">\n<h3>Why it matters<\/h3>\nIt connects ancient chess masters, manuscript culture, modern endgame theory, and computational tablebase analysis.\n\n<\/div>\n<\/div>\n<\/div>\n<figure class=\"suli-main-diagram\"><img decoding=\"async\" src=\"https:\/\/shatranj.ai\/wp-content\/uploads\/2026\/04\/suli_diamond_shatranj_chess_puzzle_diagram.png\" alt=\"Diagram of Suli\u2019s Diamond canonical shatranj (old chess) position, White to move and win.\" \/><figcaption class=\"suli-main-diagram-caption\">\n<h3>Suli\u2019s Diamond, canonical position<\/h3>\nWhite to move and win.\n\n<code class=\"suli-fen\">8\/8\/8\/3k4\/8\/1KQ5\/8\/q7 w<\/code>\n\n<\/figcaption><\/figure>\n<\/div>\n<div class=\"suli-callout\">\n\nHistorical note: as-Suli presented the problem as an ancient and exceptionally difficult position. Modern research shows that the puzzle was not merely a charming legend: it contains a deep forcing method that remained difficult even for later chess experts.\n\n<\/div>\n<\/section><section id=\"watch\" class=\"suli-section\">\n<h2>Watch the full documentary lecture<\/h2>\n<p class=\"suli-lead\">Start with the video to understand why this small four-piece position became one of the great mysteries of chess history. The lecture follows Suli\u2019s Diamond from the Abbasid world to the Istanbul and Cairo manuscript tradition, then through von der Linde, Murray, Averbakh, Beasley, Hans Ree, John Tromp, and the new Suli-Karatekin reverse-ferz discoveries.<\/p>\n\n<div class=\"suli-video\"><iframe title=\"Suli\u2019s Diamond: The 1000-year unsolved chess mystery\" src=\"https:\/\/www.youtube.com\/embed\/bGkTPnGkQ6w\" allowfullscreen=\"allowfullscreen\"><\/iframe><\/div>\n<\/section><section id=\"contents\" class=\"suli-section\">\n<h2>Video contents<\/h2>\n<p class=\"suli-lead\">Use this chapter guide to navigate the main historical and technical sections of the video before exploring the full family of related positions.<\/p>\n\n<div class=\"suli-chapters\">\n<div class=\"suli-chapter\">\n\n<span class=\"suli-time\">0:00<\/span>\n<h3>The 1000-year mystery<\/h3>\nAn introduction to Suli\u2019s Diamond as a legendary chess and shatranj puzzle with a thousand-year reputation.\n\n<\/div>\n<div class=\"suli-chapter\">\n\n<span class=\"suli-time\">1:51<\/span>\n<h3>Abbasid chess culture<\/h3>\nThe world of early shatranj masters, court culture, scholarship, and the first books on chess.\n\n<\/div>\n<div class=\"suli-chapter\">\n\n<span class=\"suli-time\">4:50<\/span>\n<h3>Wheat and the chessboard<\/h3>\nThe famous mathematical story that links chess with exponential growth and early computational imagination.\n\n<\/div>\n<div class=\"suli-chapter\">\n\n<span class=\"suli-time\">5:38<\/span>\n<h3>The Istanbul manuscript<\/h3>\nThe manuscript tradition behind Suli\u2019s Diamond and the three related positions used to reconstruct the puzzle.\n\n<\/div>\n<div class=\"suli-chapter\">\n\n<span class=\"suli-time\">10:14<\/span>\n<h3>von der Linde and Murray<\/h3>\nHow modern chess historians preserved and transmitted the historical record of the puzzle.\n\n<\/div>\n<div class=\"suli-chapter\">\n\n<span class=\"suli-time\">12:22<\/span>\n<h3>The wrong modern solution<\/h3>\nThe first Oxford Companion attempt and why it missed Black\u2019s strongest defensive idea.\n\n<\/div>\n<div class=\"suli-chapter\">\n\n<span class=\"suli-time\">13:09<\/span>\n<h3>Yuri Averbakh<\/h3>\nAverbakh\u2019s reconstruction confirmed the depth of as-Suli\u2019s ancient challenge and restored its endgame logic.\n\n<\/div>\n<div class=\"suli-chapter\">\n\n<span class=\"suli-time\">15:55<\/span>\n<h3>John Beasley and computers<\/h3>\nComputer-assisted analysis refined the solution and identified stronger defensive resources.\n\n<\/div>\n<div class=\"suli-chapter\">\n\n<span class=\"suli-time\">17:29<\/span>\n<h3>Hans Ree and the name<\/h3>\nThe Max Euwe Center conference and Hans Ree\u2019s essay helped popularize the modern name \u201cSuli\u2019s Diamond.\u201d\n\n<\/div>\n<div class=\"suli-chapter\">\n\n<span class=\"suli-time\">20:03<\/span>\n<h3>Suli-Tromp Rough Diamond<\/h3>\nJohn Tromp discovered a harder related diamond with a 53-ply solution.\n\n<\/div>\n<div class=\"suli-chapter\">\n\n<span class=\"suli-time\">21:02<\/span>\n<h3>Recap so far<\/h3>\nA brief review of how the puzzle moved from medieval manuscript culture into modern chess history and computer-assisted analysis.\n\n<\/div>\n<div class=\"suli-chapter\">\n\n<span class=\"suli-time\">21:55<\/span>\n<h3>Retroanalysis and missing pieces<\/h3>\nSmullyan-style logic puzzles inspired a new look at missing-piece reconstruction in Suli\u2019s Diamond.\n\n<\/div>\n<div class=\"suli-chapter\">\n\n<span class=\"suli-time\">22:47<\/span>\n<h3>Suli\u2019s Little Diamond<\/h3>\nA newly observed reverse-ferz variant with a compact diamond maneuver and an 11-ply win.\n\n<\/div>\n<div class=\"suli-chapter\">\n\n<span class=\"suli-time\">24:07<\/span>\n<h3>Suli\u2019s Flipped Diamond<\/h3>\nA swapped-piece version of the position that still wins, this time through a 25-ply solution.\n\n<\/div>\n<div class=\"suli-chapter\">\n\n<span class=\"suli-time\">24:49<\/span>\n<h3>The reverse-ferz secret<\/h3>\nThe British Museum manuscript position led to a deeper investigation of reverse-ferz endgames.\n\n<\/div>\n<div class=\"suli-chapter\">\n\n<span class=\"suli-time\">26:32<\/span>\n<h3>Suli\u2019s Tough Diamond<\/h3>\nThe hardest reverse-ferz diamonds reach 63 plies, more than 50% longer than the canonical study.\n\n<\/div>\n<div class=\"suli-chapter\">\n\n<span class=\"suli-time\">28:29<\/span>\n<h3>AI and tablebases<\/h3>\nThe shatranj.ai curriculum teaches the solution through dynamic programming and tablebase generation.\n\n<\/div>\n<div class=\"suli-chapter\">\n\n<span class=\"suli-time\">29:33<\/span>\n<h3>The solution<\/h3>\nThe full solution demonstrates opposition, zugzwang, corresponding squares, and precise long-range maneuvering.\n\n<\/div>\n<div class=\"suli-chapter\">\n\n<span class=\"suli-time\">49:06<\/span>\n<h3>Further projects<\/h3>\nConnections to the \u015eAH\u00ce chess set, Deep Sea Chess, TEDxBoston, and the shatranj.art digital exhibit.\n\n<\/div>\n<\/div>\n<\/section><section class=\"suli-section\">\n<h2>Why shatranj.ai studies Suli\u2019s Diamond<\/h2>\n<p class=\"suli-lead\">Suli\u2019s Diamond is more than a historical curiosity. It is a bridge between cultural heritage and artificial intelligence. In the shatranj.ai curriculum, students can study the puzzle historically, then learn how dynamic programming, retrograde analysis, and endgame tablebases can verify solutions that challenge even expert human intuition.<\/p>\n\n<div class=\"suli-grid\">\n<div class=\"suli-card\">\n<h3>History<\/h3>\nStudents encounter Abbasid science, early chess literature, manuscript transmission, and the intellectual world of as-Suli.\n\n<\/div>\n<div class=\"suli-card\">\n<h3>Endgame thinking<\/h3>\nThe puzzle teaches opposition, zugzwang, corresponding squares, and long forcing plans.\n\n<\/div>\n<div class=\"suli-card\">\n<h3>Artificial intelligence<\/h3>\nThe position becomes a compact laboratory for dynamic programming, search, and tablebase construction.\n\n<\/div>\n<\/div>\n<\/section><section id=\"positions\" class=\"suli-section\">\n<h2>The Suli\u2019s Diamond family<\/h2>\n<p class=\"suli-lead\">After watching the story of Suli\u2019s Diamond, you can explore the actual positions behind the video. The original puzzle is now understood as the center of a wider family of related shatranj endgame studies: the canonical Suli\u2019s Diamond, John Tromp\u2019s Rough Diamond, and the newer reverse-ferz Suli-Karatekin Diamonds discovered through tablebase analysis.<\/p>\n\n<div class=\"suli-play-callout\">\n<h3>Try these positions yourself<\/h3>\nCopy any FEN below and paste it into the shatranj.ai play and study tool. You can explore the positions, test moves, and study the difference between regular-ferz and reverse-ferz diamonds.\n\n<a href=\"https:\/\/play.shatranj.ai\" target=\"_blank\" rel=\"noopener\">Open play.shatranj.ai<\/a>\n\n<\/div>\n<div class=\"suli-position-grid\"><article class=\"suli-position-card\"><img decoding=\"async\" src=\"https:\/\/shatranj.ai\/wp-content\/uploads\/2026\/04\/suli_diamond_shatranj_chess_puzzle_diagram.png\" alt=\"Suli\u2019s Diamond canonical shatranj position, White wins in 39 plies\" \/>\n<div class=\"suli-position-body\">\n<h3>Suli\u2019s Diamond<\/h3>\n<p class=\"suli-position-subtitle\">Canonical position<\/p>\nThe classic four-piece shatranj study associated with as-Suli. White must capture the black ferz on a1 without losing the white ferz to a counterattack.\n<div class=\"suli-meta\">White to move and win in 39 plies<\/div>\n<code class=\"suli-fen\">8\/8\/8\/3k4\/8\/1KQ5\/8\/q7 w<\/code>\n\n<\/div>\n<\/article><article class=\"suli-position-card\"><img decoding=\"async\" src=\"https:\/\/shatranj.ai\/wp-content\/uploads\/2026\/04\/suli_tromp_rough_diamond_cropped.png\" alt=\"Suli-Tromp Rough Diamond shatranj position, White wins in 53 plies\" \/>\n<div class=\"suli-position-body\">\n<h3>Suli-Tromp Rough Diamond<\/h3>\n<p class=\"suli-position-subtitle\">John Tromp\u2019s harder related diamond<\/p>\nA harder transpositional relative discovered by John Tromp. With best play, it leads into the classical Suli\u2019s Diamond idea after a longer forcing route.\n<div class=\"suli-meta\">White to move and win in 53 plies<\/div>\n<code class=\"suli-fen\">3Q3k\/8\/8\/K7\/8\/8\/8\/q7 w<\/code>\n\n<\/div>\n<\/article><article class=\"suli-position-card\"><img decoding=\"async\" src=\"https:\/\/shatranj.ai\/wp-content\/uploads\/2026\/04\/suli_karatekin_tough_diamond_cropped.png\" alt=\"Suli-Karatekin Tough Diamond reverse-ferz shatranj position, White wins in 63 plies\" \/>\n<div class=\"suli-position-body\">\n<h3>Suli-Karatekin Tough Diamond<\/h3>\n<p class=\"suli-position-subtitle\">Reverse-ferz diamond<\/p>\nOne of the hardest known members of the Suli\u2019s Diamond family. In this reverse-ferz setting, the two ferzes move on opposite diagonal complexes and cannot capture each other.\n<div class=\"suli-meta\">White to move and win in 63 plies<\/div>\n<code class=\"suli-fen\">5k2\/8\/8\/2Q4K\/8\/8\/8\/5q2 w<\/code>\n\n<\/div>\n<\/article><article class=\"suli-position-card\"><img decoding=\"async\" src=\"https:\/\/shatranj.ai\/wp-content\/uploads\/2026\/04\/suli_little_diamond_cropped.png\" alt=\"Suli\u2019s Little Diamond reverse-ferz shatranj position, White wins in 11 plies\" \/>\n<div class=\"suli-position-body\">\n<h3>Suli\u2019s Little Diamond<\/h3>\n<p class=\"suli-position-subtitle\">Missing-piece variation<\/p>\nA compact reverse-ferz study inspired by the manuscript question of the missing ferz. The winning idea begins with Ferz b4 and creates a small diamond-shaped maneuver.\n<div class=\"suli-meta\">White to move and win in 11 plies<\/div>\n<code class=\"suli-fen\">8\/8\/8\/3k4\/8\/1KQ5\/8\/1q6 w<\/code>\n\n<\/div>\n<\/article><article class=\"suli-position-card\"><img decoding=\"async\" src=\"https:\/\/shatranj.ai\/wp-content\/uploads\/2026\/04\/suli_flipped_diamond_cropped.png\" alt=\"Suli\u2019s Flipped Diamond reverse-ferz shatranj position, White wins in 25 plies\" \/>\n<div class=\"suli-position-body\">\n<h3>Suli\u2019s Flipped Diamond<\/h3>\n<p class=\"suli-position-subtitle\">Swapped shah and ferz version<\/p>\nA related reverse-ferz position created by swapping the black shah and ferz. White still wins, again beginning with the key move Ferz b4.\n<div class=\"suli-meta\">White to move and win in 25 plies<\/div>\n<code class=\"suli-fen\">8\/8\/8\/3q4\/8\/1KQ5\/8\/1k6 w<\/code>\n\n<\/div>\n<\/article><article class=\"suli-position-card\"><img decoding=\"async\" src=\"https:\/\/shatranj.ai\/wp-content\/uploads\/2026\/04\/suli_karatekin_concave_tough_diamond_cropped.png\" alt=\"Suli-Karatekin Concave Tough Diamond reverse-ferz shatranj position, White wins in 63 plies\" \/>\n<div class=\"suli-position-body\">\n<h3>Suli-Karatekin Concave Tough Diamond<\/h3>\n<p class=\"suli-position-subtitle\">Concave reverse-ferz diamond<\/p>\nAnother 63-ply reverse-ferz position from the Suli-Karatekin Diamond family. Its geometry shows how the ancient puzzle expands into a larger landscape of difficult endgame studies.\n<div class=\"suli-meta\">White to move and win in 63 plies<\/div>\n<code class=\"suli-fen\">8\/5q2\/8\/8\/8\/8\/3K4\/Q4k2 w<\/code>\n\n<\/div>\n<\/article><\/div>\n<\/section><section class=\"suli-section\">\n<h2>Read, watch, play, and study<\/h2>\n<div class=\"suli-links\"><a class=\"suli-linkbox\" href=\"https:\/\/doi.org\/10.5281\/zenodo.19465731\" target=\"_blank\" rel=\"noopener\"><strong>Read the full Zenodo paper<\/strong>Suli-Karatekin Diamonds and the hardest reverse-ferz positions.<\/a>\n<a class=\"suli-linkbox\" href=\"https:\/\/www.youtube.com\/watch?v=bGkTPnGkQ6w\" target=\"_blank\" rel=\"noopener\"><strong>Watch the Suli\u2019s Diamond video<\/strong>Historical lecture with transcript, chapters, and solution discussion.<\/a>\n<a class=\"suli-linkbox\" href=\"https:\/\/www.arves.org\/arves\/index.php\/en\/halloffame\/1814-sulis-diamond\" target=\"_blank\" rel=\"noopener\"><strong>View the ARVES reference page<\/strong>Endgame study reference page linking the position family and paper.<\/a>\n<a class=\"suli-linkbox\" href=\"https:\/\/lms.shatranj.ai\" target=\"_blank\" rel=\"noopener\"><strong>Study Lesson 16 in the shatranj.ai curriculum<\/strong>Dynamic programming, tablebase generation, and Suli\u2019s Diamond coding materials.<\/a>\n<a class=\"suli-linkbox\" href=\"https:\/\/play.shatranj.ai\" target=\"_blank\" rel=\"noopener\"><strong>Try the puzzles on play.shatranj.ai<\/strong>Set up shatranj positions and explore FEN-based studies.<\/a>\n<a class=\"suli-linkbox\" href=\"https:\/\/shatranj.ai\/publications\/\" target=\"_blank\" rel=\"noopener\"><strong>Visit shatranj.ai publications<\/strong>Research outputs and project publications related to chess, shatranj, and AI.<\/a><\/div>\n<\/section><section class=\"suli-section suli-faq\">\n<h2>Frequently asked questions<\/h2>\n<details><summary>Is Suli\u2019s Diamond a chess puzzle or a shatranj puzzle?<\/summary>It is a shatranj puzzle. Shatranj is the historical form of chess in which the ferz, the ancestor of the modern queen, moves and attacks only one square diagonally. Also, to win, capturing all of opponents pieces while keeping at least one non-shah piece of your own is sufficient: checkmate is not necessary.\n\n<\/details><details><summary>Why is the puzzle called a diamond?<\/summary>The modern metaphorical name primarily reflects the intellectual beauty of the canonical endgame composition and the enduring 1000-year unsolved challenge of As-Suli. Later, it was discovered that to win the Suli&#8217;s Little Diamond position a compact diamond maneuver with the ferz was necessary. Also, the Suli-Karatekin Tough Diamond family has 24 diamond shape piece compositions, which made the diamond geometry more visible.\n\n<\/details><details><summary>Who solved Suli\u2019s Diamond?<\/summary>The historical record found in 3 manuscripts, as narrated by Hans Ree through Averbakh during the 1993 Max Euwe Center&#8217;s conference with chess historians, suggests that top endgame authorities of modern chess agree that as-Suli understood the essential winning idea, otherwise he wouldn&#8217;t have been able to make such a bold claim. Yuri Averbakh reconstructed the clues left in these 3 diagrams into a complete solution and confirmed it in modern chess literature, and John Beasley\u2019s computer-assisted analysis refined the strongest defense. Later, John Tromp found a transposed position through computer assistance that shows there is a harder version Suli&#8217;s Diamond that transposes to the canonical version after best play from both sides. Finally, the diagram in the 4th manuscript with reverze ferz piece composition has been revealed to have a hidden difficulty by Tamer Karatekin and that Black needs to play accurately a series of single moves to achieve a draw. So in all these 4 positions the judgement of As-Suli was correct as to the game result, he did also provide the first few moves of the solution. The complete solutions were later discovered through human analysis and confirmed with computer assistance.\n\n<\/details><details><summary>What are Suli-Karatekin Diamonds?<\/summary>They are newly discovered reverse-ferz relatives of Suli\u2019s Diamond. In these positions, the ferzes move on opposite diagonal complexes and cannot capture each other. The hardest examples reach 63 plies, while the canonical Suli&#8217;s diamond was 39 ply and all same-ferz positions in shah+ferz vs shah+ferz endgames can maximally reach a 53 ply solution as shown by John Tromp. So the Suli-Karatekin diamonds are the toughest ones.\n\n<\/details><details><summary>Where can I find the complete solution?<\/summary>The full solution and detailed analysis are available through the Zenodo paper, the ARVES reference page, and Lesson 16 of the shatranj.ai curriculum.\n\n<\/details><\/section><\/div>\n<script type=\"application\/ld+json\">{\"@context\":\"https:\/\/schema.org\",\"@type\":\"EducationalWebPage\",\"name\":\"Suli\u2019s Diamond: The 1000-Year Shatranj Puzzle\",\"description\":\"A concise guide to Suli\u2019s Diamond, the legendary shatranj endgame puzzle of as-Suli, including its history, solution, video lecture, FEN positions, AI tablebase analysis, and Suli-Karatekin Diamonds.\",\"url\":\"https:\/\/shatranj.ai\/suli-diamond\/\",\"about\":[\"Suli\u2019s Diamond\",\"as-Suli\",\"Shatranj\",\"Chess history\",\"Endgame tablebase\",\"Dynamic programming\",\"Artificial intelligence education\"],\"author\":{\"@type\":\"Person\",\"name\":\"Tamer Karatekin\",\"url\":\"https:\/\/shatranj.ai\"},\"publisher\":{\"@type\":\"Organization\",\"name\":\"Shatranj.ai\",\"url\":\"https:\/\/shatranj.ai\"},\"video\":{\"@type\":\"VideoObject\",\"name\":\"Suli\u2019s Diamond: The 1000-year unsolved chess mystery\",\"embedUrl\":\"https:\/\/www.youtube.com\/embed\/bGkTPnGkQ6w\",\"contentUrl\":\"https:\/\/www.youtube.com\/watch?v=bGkTPnGkQ6w\",\"description\":\"A historical and computational lecture on Suli\u2019s Diamond, its manuscript sources, solution, and newly discovered harder variants.\"}}<\/script>\n<script type=\"application\/ld+json\">{\"@context\":\"https:\/\/schema.org\",\"@type\":\"FAQPage\",\"mainEntity\":[{\"@type\":\"Question\",\"name\":\"Is Suli\u2019s Diamond a chess puzzle or a shatranj puzzle?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"Suli\u2019s Diamond is a shatranj puzzle. Shatranj is the historical form of chess in which the ferz, the ancestor of the modern queen, moves and captures only one square diagonally.\"}},{\"@type\":\"Question\",\"name\":\"Why is the puzzle called a diamond?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"The modern metaphorical name reflects both the beauty of the study and the geometric feeling of the long king-and-ferz maneuver. Later related positions make the diamond geometry even more visible. According to chess columnist Hans Ree, the name was first mentioned by Yuri Averbakh at the Max Euwe Center's conference for chess historians in 1993.\"}},{\"@type\":\"Question\",\"name\":\"Who solved Suli\u2019s Diamond?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"The historical record suggests that as-Suli understood the essential winning idea and shared 3 separate positions with correct analysis along the route to the win. Yuri Averbakh later reconstructed and confirmed the solution in modern chess literature, and John Beasley\u2019s computer-assisted analysis refined the strongest defense. John Tromp provided a retrograde analysis C code , which he used to discover a rougher form of Suli's Diamond, where with best play from bot sides, the position transposes into Suli's Diamond puzzle, thus extending the whole solution from 39 to 53 plies. Later, Tamer Karatekin showed that the 4th manuscript diagram from British Museum pointed out by chess historian Murray on referze-ferz version of Suli's Diamond was much trickier than originally thought, it was Suli's Hidden Gem, with a tricky defense to achieve draw.\"}},{\"@type\":\"Question\",\"name\":\"What are Suli-Karatekin Diamonds?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"Suli-Karatekin Diamonds are newly discovered reverse-ferz relatives of Suli\u2019s Diamond. In these positions, the ferzes move on opposite diagonal complexes and cannot capture each other. The hardest examples reach 63 plies, compared to 39 in the canonical Suli's Diamond.\"}}]}<\/script>\n\n<\/section>\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t","protected":false},"excerpt":{"rendered":"<p>Shatranj \u2022 Chess history \u2022 Artificial intelligence Suli\u2019s Diamond Suli\u2019s Diamond is the mysterious 1000-year unsolved chess puzzle associated with the challenge of the legendary chess master as-Suli. Preserved through medieval manuscripts and later reconstructed by modern historians, endgame experts, and computer analysis, it remains one of the most beautiful intellectual challenges in chess history. [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-1538","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/shatranj.ai\/de\/wp-json\/wp\/v2\/pages\/1538","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/shatranj.ai\/de\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/shatranj.ai\/de\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/shatranj.ai\/de\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/shatranj.ai\/de\/wp-json\/wp\/v2\/comments?post=1538"}],"version-history":[{"count":53,"href":"https:\/\/shatranj.ai\/de\/wp-json\/wp\/v2\/pages\/1538\/revisions"}],"predecessor-version":[{"id":1610,"href":"https:\/\/shatranj.ai\/de\/wp-json\/wp\/v2\/pages\/1538\/revisions\/1610"}],"wp:attachment":[{"href":"https:\/\/shatranj.ai\/de\/wp-json\/wp\/v2\/media?parent=1538"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}